The widower of Brittany Murphy was found dead at the home the couple once shared in the Hollywood Hills. The Los Angeles Police Department tells ET Simon Monjack was pronounced dead late Sunday night after suffering a heart attack.

A 911 call was placed to come to the aid of Monjack at 9 p.m. on Sunday night. Resuscitation efforts failed and Monjack passed away from cardiac arrest. Sgt. Louie Lozano of the Los Angeles Police Department told ET that detectives are on the scene to conduct an investigation. Pending further investigation, police tell ET that detectives believe he died of natural causes.

Late wife Brittany Murphy died on December 20, 2009 from pneumonia, with other conditions contributing but not directly related to the immediate cause of death: iron deficiency anemia and multiple drug intoxication.